Rabbiteye blueberry cultivar Snowflake

ABSTRACT

Description and specifications of a new and distinct rabbiteye blueberry variety which originated from seed produced by a hand-pollinated cross of Florida K and NC 1830 is provided. The new rabbiteye blueberry variety can be distinguished from all others by its low chilling requirement and its combination of late flowering with early ripening.

SUMMARY OF THE INVENTION

The new and distinct variety of rabbiteye blueberry originated from ahand pollinated cross of Florida - K×NC 1830 made in 1981 at the FloridaAgricultural Experiment Station experimental blueberry greenhouse inGainesville, Fla. The seeds resulting from this controlled hybridizationwere germinated in a greenhouse during the winter of 1981-1982.Resulting seedlings were planted in the spring of 1982 in a field on theUniversity of Florida Horticultural Unit at Gainesville Fla. Theseedlings fruited in the spring of 1984 and one, designated FL 84-106,was selected for its outstanding fruit quality and early ripening, ascompared to other known varieties.

During 1984, the original plant selection was propagated asexually byrooting softwood cuttings, and a test planting of 15 plants wasestablished. Other rooted cuttings of this clone have been grown in theUniversity of Florida blueberry breeding greenhouse to obtaininformation on fertility and fruit quality under greenhouse conditions.

The new variety has been asexually propagated on at least three otheroccasions by softwood cuttings. It roots readily from softwood cuttingsand grows well in the cutting nursery. In all cases in which the clonehas been propagated by cuttings, the vegetative and fruitcharacteristics of the original plant have been maintained.

Bushes of the new variety are vigorous and upright in growth. Plants seton a soil of intermediate fertility were 170 cm after five years.Sprouts from the plants were arising from a band 120 cm wide fromsix-year old plants and the drip line of the canopy was 220 cm wide. Theplant produces basal shoots in sufficient quantities to renew the plantas it grows. Because Snowflake prolifically sprouts from the base bymeans of rhizome budding, pruning or mowing will be needed to maintainthe narrow base necessary for mechanical harvesting. After six to eightyears, top hedging or selective cane removal is needed to preventexcessive plant height. The number of flower buds produced is aboutaverage for rabbiteye blueberry cultivars and is sufficient to produce aheavy crop. Plants of the new variety flower one week before theyproduce new leaves in the spring, and foliation has always beenexcellent.

Plants of the new variety appear to be above average for a rabbiteyeblueberry in tolerance to Phytophthora root rot. Neither cane canker,incited by Botryosphaeria corticus, nor stem blight, incited byBotryosphaeria dothedia, has been a problem in the field plantings.Resistance to Botrytis blight, incited by Botrytis cinerea, has beenequal to or greater than that of most other rabbiteye cultivars plantedin the same test field. Leaf retention is good in the fall, indicatingsatisfactory levels of tolerance to the various species of defoliatingfungal pathogens prevalent in the experimental area.

The new variety has a low chilling requirement, and has not showndelayed flowering of leafing in Gainesville, Fla. following winters with300 total hours with temperatures below 7° C. On the other hand, thevariety tends to hold its dormancy well during warm periods during thewinter, and is thus less prone to spring frost damage than otherearly-ripening rabbiteye blueberry varieties. The fruit ripenexceptionally early for a rabbiteye blueberry, due to a very shortflowering-to-ripening interval. Ripening date averages 10 days earlierthan Beckyblue, which is the earliest-ripening rabbiteye cultivar nowavailable, and 15 days earlier than Climax, another rabbiteye varietywidely grown because of its early ripening. Yet, the average date offull bloom for the new variety is more than two weeks later than forBeckyblue and more than one week later than Climax. The average date offirst commercial harvest on plants of the new variety grown in northcentral Florida will be about May 10, and midharvest will be about May18. Harvest dates are about ten days later than for the highbush varietyMarimba. Varieties recommended for cross-pollination of Snowflakeinclude Climax, Brightwell, Woodward, and Bluebelle.

Fruit of the new variety are large, dark-blue in color, and possess amoderately heavy surface wax. Firmness is medium to poor, acharacteristic which will make this variety best suited to localmarketing. The stem scar is medium in size, and the flavor is good andsimilar to that of the major rabbiteye varieties. Seediness and skinthickness are about average for a rabbiteye blueberry cultivar. Thefruit detach readily from the plant when ripe, and are easy to harvestby hand.

Windy has 72 chromosomes in each somatic cell and is distinguished fromMarimba which has 48 chromosomes in each somatic cell.

The new variety has been named the SNOWFLAKE cultivar.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying photographs show typical specimens of the fruit andleaf of the new variety in color as nearly true as it is reasonablypossible to make in a color illustration of this character.

DETAILED DESCRIPTION OF THE NEW VARIETY

The following is a detailed description of the pomologicalcharacteristics of the subject blueberry clone. Where dimensions, sizes,colors, and other characteristics are given, it is to be understood thatsuch characteristics are approximations of averages set forth asaccurately as practicable.

The description reported herein is from specimens grown in Gainesville,Fla.

Plant:

Size.--Medium 170 cm tall and sprouting from a base 120 cm in a diameterafter five years in field plots.

Time of 50% anthesis.--March 6.

Growth.--Medium to high vigor, cessation of growth in early October.Plant more upright than spreading.

Productivity.--Medium to high. Young plants precocious.

Cold hardiness.--Plant and dormant flower buds hardy to below -13° C.Flowers and fruits hardy to -2° C.

Chilling requirement.--The plant requires only 300 hours duration oftemperatures at or below 7° C. to induce normal leafing and flowering inthe spring.

Stems.--Moderately upright. Readily produces new sprouts from rhizomes.On five-year old plants growing in the field, length of the terminalgrowth in one season is 25 cm for mature stems and 80 cm for renewalstems.

Internode length.--1.2 cm. Color of 1-year-old stems -- red pink (10A,Plate 13 in Maerz, A, and M. R. Paul (1950) "A Dictionary of Color", 2dEd.).

Disease resistance.--Moderate resistance to Phytophthora root rot, stemblight, powdery mildew, Botrytis flower blight, and various defoliatingleaf diseases. High resistance to cane canker.

Foliage:

Leaves.--Color -- mature leaves green (9C, Plate 25, Dictionary ofColor, supra). Leaf margins serrulate. Leaves glabrous except for a veryfew stalked glands on lower surface. Leaves average 34 mm wide×56 mmlong.

Flowers:

Date of 50% anthesis.--March 6.

Flower color.--White.

Flower shape.--Urceolate Mean corolla length: 9 mm; width: 7 mm; meandiameter of corolla tube aperture: 3 mm.

Flower bud number.--Medium to high. Mean number of flowers per cluster--10.

The variety is highly self-incompatible.

Fruit:

Maturity.--First harvest May 10. Mid harvest May 18.

Size of berry.--Medium large. Average weight 1.70 g. Calyx cup 4 mmdeep. Berry averages 12 mm tall and 13 mm in diameter.

Berry color.--Dark blue (6A, Plate 48, Dictionary of Color, supra), withmoderate surface wax.

Fruit stem scar.--Medium to good.

Berry firmness.--Poor to medium. Firmer than berries from cultivarWoodard; similar in firmness to cultivar Premier.

Berry flavor and texture.--Flavor sweet with moderate acid level. Skinsof normal thickness and seeds of normal size and number for rabbiteyecultivars.

Storage quality.--Medium.

Uses.--Primarily for customer-pick and local markets. Also suitable forprocessing.

Suitability for mechanical harvest.--Low due to the lack of berryfirmness.

The Variety

The most distinctive feature of the variety is its combination of earlyripening and late flowering. The variety flowers more than 2 weeks laterbut ripens 10 days earlier than the earliest-ripening rabbiteyeblueberry variety now available. It produces a high-quality fruit thatare suitabe for customer-pick and local markets.

I claim:
 1. A new and distinct variety of rabbiteye blueberry plant,substantially as illustrated and described, characterized by its lateflowering, early ripening, vigorous, disease-resistant bush, and lowchilling requirement.